What happened to the sirens on police station roofs?

Question

On the top of police stations and government buildings, there used to be red or green sirens to give the four-minute warning for war, but they were taken down. Has anything replaced them?
Alan, Clayhall

Answer

** Definitive **
Name: Chris, Cobham
Qualification: 1960s Police Officer
Answer: They were discontinued in the late 1960s when the civil descent was disbanded. Nowadays, there is nothing that replaces it, as the thinking was that there was little we could do in four minutes before we were vaporised. Sirens are still in place for some fire service sirens.